Abstract Off-road motorcycles transit over significantly irregular terrains facilitated by their suspension system. The optimisation of their suspension is an open topic. On one hand, on-road motorcycles need to be extended to consider off-road peculiarities such as larger amplitude of motion and a standing rider, to provide optimisation predictions. On the other hand, an objective methodology to verify the predictions is needed since the current practice is to rely on the subjective perception of the rider. In this article, we addressed for the first time, the second problem by developing an estimator of contact forces based on inverse dynamics equations and kinematic measurements. First, in a virtual experiment, it was verified that the estimation is satisfactory. Subsequently, using data recorded at a motocross track, we showed that the estimated forces vary consistently with the obstacles in the track. This provides an objective and consistent indication of the performance of the motorcycle and hence can be used to verify optimisations.

中文翻译：

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越野摩托车轮胎力估算

摘要 越野摩托车在悬挂系统的帮助下在明显不规则的地形上行驶。悬架的优化是一个开放的话题。一方面，需要扩展公路摩托车以考虑越野特性，例如较大的运动幅度和站立的骑手，以提供优化预测。另一方面，需要一种客观的方法来验证预测，因为当前的做法是依赖于骑手的主观感知。在本文中，我们通过开发基于逆动力学方程和运动学测量的接触力估计器，首次解决了第二个问题。首先，在虚拟实验中，验证了估计是令人满意的。随后，使用记录在越野摩托车赛道上的数据，我们表明，估计的力随轨道中的障碍物而变化。这提供了摩托车性能的客观和一致的指示，因此可用于验证优化。